Apparatus and method for application of a pharmaceutical to the tympanic membrane for photodynamic laser myringotomy

ABSTRACT

A packaged kit for performing a photodynamic laser myringotomy includes a plurality of ear needles having different shaped absorbent applicators on distal ends of the needles, a vial of a single dose of an otologic formulation of mitomycin-C, a diluent carrier containing sterilized water, and a syringe. The component parts of the kit are used together to reconstitute the contents of the vial with the water in the diluent carrier, and then draw the reconstituted drug into the syringe. A selected one of the plurality of ear needles is then communicated with the syringe. The syringe and needle are then used to inject the reconstituted drug into the absorbent pad at the end of the needle, and the absorbent pad containing the drug is used to apply the drug to the tympanic membrane. The application of the drug to the tympanic membrane prepares the membrane for a myringotomy procedure, and in particular, a photodynamic laser myringotomy.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention pertains to an apparatus and method for applying apharmaceutical to the tympanic membrane in preparation for performing aphotodynamic laser myringotomy. In particular, the present inventionpertains to a packaged kit that includes a plurality of ear needleshaving different shaped absorbent applicators on distal ends of theneedles, a vial of a single dose of an otologic formulation ofmitomycin-C, a diluent carrier containing sterilized water, and asyringe. The component parts of the apparatus are used together toreconstitute the contents of the vial with the water in the diluentcarrier, and then draw the reconstituted drug into the syringe. Aselected one of the plurality of ear needles is then communicated withthe syringe. The syringe and needle are then used to inject thereconstituted drug into the absorbent pad at the end of the needle, anduse the absorbent pad containing the drug to apply the drug to thetympanic membrane. The application of the drug to the tympanic membraneprepares the membrane for a myringotomy procedure, and in particular, aphotodynamic laser myringotomy.

2. Description of the Related Art

A myringotomy, which is a surgical puncture of the ear tympanic membraneor ear drum, is the most often performed procedure for relievingrecurrent acute otitis media (RAOM), or recurrent ear infectionsresulting from fluid build-up in the middle ear. Recurrent acute otitismedia is the most common reason for children's visits to physicians andresults in more than 600,000 myringotomy procedures annually in theUnited States alone. Myringotomy is the single-most common surgicalprocedure performed on patients under the age of 15.

However, myringotomy alone often will not result in the sustained reliefof the infection. In order to relieve the infection, the opening in theear drum that allows for the fluid drainage must remain open for anextended period of time. This allows for ventilation of the ear canaland the resolution of the infection. The myringotomy opening through theear drum is kept open by the implantation of a pressure equalizationtube in the ear drum. The insertion of the tube through the ear drumallows drainage of the fluid in the middle ear that is the source of theear infection. The ear tube is typically a small plastic tube having aspool shape. While this is not a perfect solution, inserting thepressure equalization tube through the ear drum most often achieves thedesired clinical objective, the resolution of the infection.

The tube insertion is a routine procedure, and typically requires only afew minutes of the physician's time. The tube insertion can be performedas an outpatient surgery. However, because the procedure is typicallyperformed on a child, it is often necessary that the child beunconscious or under a general anesthesia in order to achieve thedesired level of compliance from the child. The need to anesthetize thechild transforms what would be a very simple clinical procedure into afully involved surgical procedure. It would be very desirable to removethe anesthesia requirement from the myringotomy procedure. With theremoval of the anesthesia requirement, a myringotomy procedure could beperformed by the physician at most any convenient location.

Myringotomies have been performed without the use of pressureequalization tubes. In these investigational myringotomy procedures, thephysician uses a lance to produce an opening in the ear drum and alsouses mitomycin-C to treat the ear drum in the area of the lanceinsertion. Mitomycin-C is an anti-metabolic agent that acts byinterrupting DNA synthesis. It has been used as a chemotherapy agent,for example, in stomach and pancreatic cancers, for many years. Itsanti-metabolic properties have prompted ophthalmologists to consider itsuse as a means of improving patency in trabeculectomy surgery. Thisprocedure is well suited for the use of mitomycin, and the use ofmitomycin in the procedure has ultimately become a standard ofphysicians.

The successful fistulae formation in glaucoma surgery with theaccompanying use of mitomycin-C has resulted in experimentation in avariety of different surgical procedures where the desired end point, afunctional, patent fistulae, is the same. Most notable among theseprocedures is the myringotomy procedure, or the surgical creation of apathway through the tympanic membrane.

A myringotomy performed with a lance and the concomitant use ofmitomycin-C has been demonstrated to provide a statistically significantincrease in the time required for closure of the fistulae formed, versusa myringotomy procedure performed without the benefit of theaccompanying use of mitomycin-C. It has been further demonstrated thatthe use of post-operative dexamethasone or an equivalentanti-inflammatory agent has further improved these results, providingdata functionally equivalent to that of a myringotomy procedureperformed with pressure equalization tube insertion.

The use of a laser for performance of a myringotomy procedure is alsowell understood. However, the use of a laser alone in the procedure isgenerally viewed as inefficient in the treatment of recurrent acuteotitis media, or ear infections due to fluid build-up in the middle ear,because the laser opening in the ear drum will not remain open longenough to achieve the desired clinical end point.

While the procedures discussed above eliminate the use of the pressureequalization tubes typically employed in myringotomy procedures, they donot address the critical issue of patient compliance and the resultantneed for anesthesia when performing a myringotomy procedure on a child.

SUMMARY OF THE INVENTION

Mitomycin-C in its natural state is purple in color. It has beenenvisioned by the inventor that the application of mitomycin-C to thetympanic membrane or ear drum in the middle ear would give the membranethe purple color of the mitomycin-C. Furthermore, suspending themitomycin-C on the tympanic membrane with a viscous agent and/or anadhesive agent mixed with the mitomycin-C would cause the site ofapplication of the mitomycin-C on the ear drum to bear the unique purplecolor of the mitomycin-C. With the specific colored mitomycin-C in placeon the tympanic membrane, a laser tuned to the specific color of themitomycin-C applied to the tympanic membrane could be used to produce aphotodynamic, selective, laser myringotomy, i.e., a pressureequalization opening through the ear drum. The effects of themitomycin-C applied to the ear drum would sustain the opening for anextended period of time, while the non-invasive nature of the laser beamused in producing the opening through the ear drum would accommodate thenon-compliant child patient population.

Thus, the present invention provides an apparatus and method for theapplication of a single dose of an otologic formulation of mitomycin-Cto the ear drum of a patient, where the mitomycin-C is suspended on theear drum by a viscous agent and/or an adhesive agent and bears aspecific color.

Furthermore, the apparatus and method of the invention make use of alaser that is specifically tuned to the color of the mitomycin-C appliedto the ear drum. The laser beam emitted by the specifically tuned laserforms an incision or opening through the ear drum at the locationtreated by the mitomycin-C.

Still further, the apparatus and method of the invention employs apackaged kit that includes a vial of the mitomycin-C, a syringe, adiluent carrier, and a plurality of ear needles with each needle havinga different-shaped absorbent pad at the needle distal end. The diluentcarrier is used to extract the mitomycin-C from the vial and mix themitomycin-C with water, forming a single dose of an otologic formulationof the mitomycin-C. The syringe extracts the single dose of mitomycin-Cfrom the diluent carrier, and a selected one of the plurality of earneedles is used with the syringe to apply the mitomycin-C to the surfaceof the tympanic membrane. The laser beam tuned to the specific color ofthe mitomycin-C applied to the tympanic membrane is then used to formthe opening through the ear drum. The mitomycin-C applied to the eardrum causes the opening formed to remain open for sufficient time toallow drainage of the fluid in the ear and the resolution of theinfection caused by the presence of the fluid.

The apparatus of the invention and its method of use discussed aboveenable a safe and simplified photodynamic laser myringotomy procedurethat is non-invasive and accommodates the non-compliant child patientpopulation.

DESCRIPTION OF THE DRAWING FIGS.

Further features of the invention are set forth in the followingdetailed description of the preferred embodiment of the invention and inthe application drawing figures.

FIG. 1 is a perspective view of the component parts of the apparatus ofthe invention and of the packaging that combines the component parts asa kit in the packaging.

FIG. 2 is a perspective view of one of the ear needles of the apparatus.

FIGS. 3 a and 3 b are views of a cone-shaped absorbent pad fixed on thedistal end of one of the ear needles.

FIGS. 4 a-d are views of a planar, kidney-shaped absorbent pad fixed onthe distal end of one of the ear needles.

FIG. 5 is a view of a cylinder-shaped absorbent pad fixed on the distalend of one of the ear needles.

FIG. 6 is a side-sectioned view of one of the ear needles with theabsorbent pad removed from the distal end.

FIG. 7 is a sectioned representation of an inner ear canal.

FIG. 8 is a representation of a portion of the inner ear canal shown inthe rectangle of FIG. 7.

FIG. 9 is a view similar to FIG. 8, but showing a pharmaceutical beingapplied to the ear drum by one of the plurality of ear needles of theapparatus.

FIG. 10 is a view similar to FIG. 9, but showing the pharmaceuticalbeing applied by another of the ear needles of the apparatus.

FIG. 11 is a view similar to FIG. 9, but showing the pharmaceuticalbeing applied by another of the ear needles of the apparatus.

FIG. 12 is a view similar to FIG. 9, but showing a laser beam ablatingthe tympanic membrane at a location treated by the pharmaceutical of theapparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

The component parts of the apparatus of the invention are shown inFIG. 1. These include the parts of the invention that enable the safeapplication of a pharmaceutical such as mitomycin-C to the tympanicmembrane, or ear drum, in an ear canal, and the assembling of thecomponent parts after their use for safe disposal. Several of thecomponent parts are known in the prior art in one form or another.Therefore, these component parts will be referred to by their commonlyunderstood names, but will not be described in detail. The materialsused to construct the component parts of the invention are those thatare most typically used for constructing similar parts.

The component parts include a vial 12 of the pharmaceutical, a syringe14, a diluent carrier 16, a plurality of ear needles 18, 22, 24, aresilient packaging block 26, a semi-rigid packaging box 28, and a sheetof packaging material 32. As stated earlier, each of these componentparts is constructed of materials typically used in manufacturingsimilar parts.

The pharmaceutical vial 12 has a construction that is known in the art.In the preferred embodiment, the pharmaceutical contained by the vial 12is a single dose of an otologic formulation of mitomycin-C. Themitomycin-C has a specific color. In its natural state, mitomycin ispurple. Like conventional pharmaceutical vials, the vial 12 has a top 34that can be pierced by a syringe needle which seals closed after theneedle is removed from the top 34.

The syringe 14 has the typical construction of a syringe. A plunger 36extends from a proximal end of the syringe body 38, and the oppositedistal end 42 of the syringe body is provided with a female luer. Theoperation of the syringe 14 is conventional.

The diluent carrier 16 in the preferred embodiment of the invention iscomprised of a second syringe 44 containing a sterile liquid such aswater, and a one-way valve 46, for example a Qosina-brand valve.However, other types of diluent carriers that perform the same functionas the diluent carrier 16 to be described could be used in the apparatuskit. In the preferred embodiment, the diluent carrier 16 containssterilized water. The amount of water provided in the carrier 16 isdetermined to mix with the pharmaceutical contained in the vial 12 toreconstitute the pharmaceutical in the carrier 16. The carrier 16 has aproximal end 46 that is adapted to receive the vial top 34. A needle(not shown) is positioned in the carrier proximal end 46 to pierce thevial top 34 and communicate the pharmaceutical contained by the vial 12with the water contained in the carrier 16. The carrier distal end 48 isadapted to communicate with the female luer at the syringe distal end42. This enables the syringe 14 to withdraw the reconstitutedpharmaceutical from the carrier 16 into the body 38 of the syringe. Asstated earlier, diluent carriers of this type are known in the art.

Each of the ear needles 18, 22, 24 have the same basic construction, theexception being the shape of the absorbent pad fixed to the needle. Eachneedle 18, 22, 24 is formed from a length of 20 gauge hypodermic tubing52 with opposite proximal 54 and distal 56 ends. An intermediate portion58 of the tubing is formed with pairs of right angles to adapt thetubing 52 for insertion into the ear canal. A standard syringe male luer62 is secured to each needle proximal end 54. The male luer 62 isadapted to attach to the female luer 42 at the syringe distal end tocommunicate the needle tubing 52 with the syringe body 38.

The three ear needles 18, 22, 24 differ from each other in that theyhave different shaped absorbent pads 68, 72, 74 at the distal ends ofthe needles. In the preferred embodiment, each of the absorbent pads 68,72, 74 is fixed to the distal ends of each of the needles 18, 22, 24. Inthe preferred embodiment, the pads 68, 72, 74 are constructed of anabsorbent material that is known in the art and is used for thetransient application of a pharmaceutical such as mitomycin-C. Each ofthe absorbent pads 68, 72, 74 is preferably constructed of polyvinylacetate (PVA) sponge material. This material rapidly absorbs liquid suchas the mitomycin-C. The dimensions of each pad 68, 72, 74 hold aspecific volume of the mitomycin-C that enables a therapeutic, singledose of the otologic formulation of mitomycin-C to be applied to thetympanic membrane of an ear.

One of the absorbent pads 68 has a cone shape that projects from theneedle distal end 56 to a tip of the cone. The cone shape of the pad 68has a center axis 76 that is coaxial with a center axis 76 of the needledistal end 56. In the preferred embodiment, the cone-shaped pad 68 has abase diameter dimension of 0.04″, and an axial length dimension of0.12″.

Another of the absorbent pads 72 has a planar configuration that extendstransverse to the center axis 76 of the needle distal end 56. This pad72 is formed in a general kidney shape. The pad 72 has a lengthdimension of 0.08″, and a width dimension of 0.04″. The pad 72 has athickness of 0.02″.

A third pad 74 has a cylindrical configuration. The center axis of thepad cylinder 74 is coaxial with the center axis 76 of the needle distalend 56. In this embodiment of the pad 74, the pad has a diameterdimension of 0.2″ and an axial length dimension of 0.4″.

Each of the above-described component parts of the apparatus iscontained in the packaging of the apparatus that includes the box 28,the resilient block 26, and the sheet of packaging material 32. Each ofthese packaging component parts is constructed of materials used in thesafe storage, transport, and disposal of pharmaceuticals and instrumentsused with pharmaceuticals such as mitomycin-C.

The block 28 is constructed of a resilient material such as foam rubber.The block 28 has a top surface 78 that is formed with a plurality ofcavities or compartments 82, 84, 86. Each of the compartments 82, 84, 86is dimensioned to receive and securely hold the vial 12, the syringe 14,the diluent carrier 16, and the plurality of ear needles 18, 22, 24. Thecompartments 82, 84, 86 securely hold the component parts of theapparatus and provide cushioning of the component parts to protect theparts during their storage and transportation.

The box 28 is dimensioned with an interior 88 that receives theresilient block 26 and securely holds the block 26 in the box interior.The box has top edges 92 that border the top opening to the box interior88. The box 28 is dimensioned so that the top edges 92 will bepositioned in the same plane as the top surface 78 of the resilientblock 26 when the block is positioned in the box interior 88.

The sheet of packaging material 32 can be any type of material currentlyused to provide a sealed enclosure of the box 28. The packaging material32 can be shrink-wrap applied around the box 28, or can be a resealablesheet of packaging material that can be peeled back from the box topedges 92 and then resealed to the top edges after the component parts ofthe apparatus have been removed from the packaging and used.

In use of the apparatus of the invention according to the method of theinvention, the packaging is first opened by removing the sheet material32 from the top edges 92 of the box. This exposes the block compartments82, 84, 86 in the block top surfaces 78. The vial 12, the syringe 14,the diluent carrier 16, and the ear needles 18, 22, 24 may be removedfrom their respective compartments in the resilient block 26.

The vial 12 of pharmaceutical, preferably mitomycin-C having a specificcolor, is then connected to the diluent carrier proximal end 46. Thiscommunicates the pharmaceutical in the vial 12 with the interior of thecarrier 16. The pharmaceutical mixes with the water in the carrier 16,reconstituting the mitomycin-C. In addition, a viscous agent and/or anadhesive agent may be mixed with the mitomycin-C in the carrier 16. Thecarrier distal end 48 is then connected to the syringe distal end 42.This communicates the reconstituted pharmaceutical in the interior ofthe carrier 16 with the interior of the syringe body 38.

Withdrawing the syringe plunger 36 from the syringe body 38 creates asuction in the syringe that draws the reconstituted pharmaceutical fromthe carrier 16 into the syringe body. After the pharmaceutical has beendrawn into the syringe body 38, the syringe 14 is disconnected from thediluent carrier 16.

A selected one of the ear needles 18, 22, 24 is next connected to thesyringe distal end 42. The choice of the ear needle 18, 22, 24 is madeby the physician determining which configuration of absorbent pad 68,72, 74 is desirable for applying the mitomycin-C to the tympanicmembrane of the patient. With the desired ear needle 18, 22, 24 securedto the syringe distal end 42, the syringe is prepared for application ofthe pharmaceutical to the tympanic membrane.

Application of the mitomycin-C to the tympanic membrane is illustratedin FIGS. 7-11. FIG. 7 shows a cross-section representation of the innerear canal 94 and the tympanic membrane 96 or ear drum in the ear canal.FIG. 8 shows an enlarged view of the portion of the ear canals 94 shownin the rectangular box of FIG. 7. In FIG. 8, a fluid buildup 98 on oneside of the ear drum 96 is a source of infection in the ear that isremoved by the method of the invention.

FIG. 9 illustrates the application of the mitomycin-C to the tympanicmembrane of the ear drum 96 by use of the absorbent pad 68 having thecone-shaped configuration. This pad 68 can be used to paint a locationon the surface of the tympanic membrane 96 with the mitomycin-C absorbedin the pad 68.

FIG. 10 illustrates the application of the mitomycin-C to a location onthe tympanic membrane 96 using the planar, kidney-shaped configuration72 of the absorbent pad. This configuration of the absorbent pad 72 canbe used to stamp a location of application of the mitomycin-C on thetympanic membrane 96.

FIG. 11 illustrates the cylindrical-shaped absorbent pad 74 being usedto appy the mitomycin-C to a location in the ear canal. Thecylindrical-shaped pad 74 is used to apply the mitomycin-C to thecircumference of the ear canal.

Each of the absorbent pads 68, 72, 74 enables an application of a singledose of an otologic formulation of mitomycin-C to the tympanic membrane96. Suspending a viscous agent or an adhesive agent in the mitomycin-Cenables the mitomycin-C to remain in situ on the tympanic membrane 96and cause anti-metabolic activity on the membrane that is localized anddefined by the specific color of the mitomycin-C, which is naturallypurple.

A laser 102 that emits a laser beam 104 that is specifically tuned tothe color of the mitomycin-C applied to the tympanic membrane 96 maythen be used to ablate the tympanic membrane tissue at a locationdefined by the specific color of the mitomycin-C applied to the tissue.The application of the specifically tuned laser beam 104 to the tympanicmembrane 96 is illustrated in FIG. 12. The laser beam 104 emitted fromthe laser 102 produces a photodynamic, selective, laser myringotomy 106.The effects of the mitomycin-C applied to the tympanic membrane 96result in a sustained patency of the myringotomy 106 opening, producedby the laser beam 104.

Thus, the apparatus of the invention and its method of use discussedabove enable a safe and simplified photodynamic laser myringotomyprocedure that is not invasive and accommodates the non-compliant childpatient population.

The apparatus of the invention and its method of use have been describedabove by reference to specific embodiments of the invention. It shouldbe understood that modifications and variations could be made to theinvention described without departing from the intended scope of thefollowing claims.

1. An apparatus for application of a pharmaceutical comprising: thepharmaceutical being a single dose of an otologic formulation ofmitomycin-C.
 2. The apparatus of claim 1, further comprising: the singledose of mitomycin-C being suspended in an agent that permeates livingtissue with the mitomycin-C.
 3. The apparatus of claim 1, furthercomprising: the single dose of mitomycin-C being suspended in a viscousagent.
 4. The apparatus of claim 1, further comprising: the single doseof mitomycin-C being suspended in an adhesive agent.
 5. The apparatus ofclaim 1, further comprising: the single dose of mitomycin-C having aspecific color.
 6. The apparatus of claim 5, further comprising: an earneedle that is adapted for receiving the single dose of mitomycin-C anddelivering the mitomycin-C to a tympanic membrane to remain in situ onthe tympanic membrane and cause anti-metabolic activity on the tympanicmembrane that is localized and defined by the specific color.
 7. Theapparatus of claim 6, further comprising: a laser that is specificallytuned to emit a laser beam that will ablate tympanic membrane tissuedefined by the specific color.
 8. The apparatus of claim 1, furthercomprising: an ear needle that is adapted for receiving the single doseof mitomycin-C and delivering the mitomycin-C to a tympanic membrane toremain in situ on the tympanic membrane and cause anti-metabolicactivity on the tympanic membrane.
 9. The apparatus of claim 8, furthercomprising: the ear needle having a tubular length with oppositeproximal and distal ends, the needle proximal end being adapted forcommunicating the needle with a syringe, and the needle distal endhaving an absorbent pad fixed to the distal end.
 10. The apparatus ofclaim 9, further comprising: the pad having a cone shape projecting fromthe needle distal end to a tip of the cone shape.
 11. The apparatus ofclaim 9, further comprising: the pad having a cylindrical shape thatprojects from the needle distal end.
 12. The apparatus of claim 9,further comprising: the needle distal end having a center axis; and, thepad being planar and being positioned transverse to the needle distalend center axis.
 13. The apparatus of claim 1, further comprising: aplurality of ear needles that are each adapted for receiving the singledose of mitomycin-C, each needle having a tubular length with oppositeproximal and distal ends, each needle proximal end being adapted forcommunicating the needle with a syringe; and, a plurality of absorbentpads fixed to the distal end of the plurality of needles, at least someof the plurality of absorbent pads having different shapes.
 14. Theapparatus of claim 13, further comprising: a tray; a lid positionableover the tray; the plurality of needles being positioned in the tray andcovered by the lid; a container of the single dose of mitomycin-Cpositioned in the tray and covered by the lid; and, a syringe positionedin the tray and covered by the lid.
 15. The apparatus of claim 14,further comprising: the tray having a plurality of separatedcompartments; the plurality of ear needles being positioned in acompartment of the tray; the container being positioned in a compartmentof the tray; and, the syringe being positioned in a compartment of thetray.
 16. The apparatus of claim 14, further comprising: a diluentcarrier positioned in a compartment of the tray.
 17. An apparatus forapplication of a pharmaceutical comprising: a container containing asingle dose of an otologic formulation of mitomycin-C; a syringe; atleast one ear needle having a tubular length with opposite proximal anddistal ends, the proximal end of the ear needle being adapted forcommunication with the syringe; at least one absorbent pad adapted forcommunication with a distal end of an ear needle; and, a packagingcontaining the container, the syringe, the ear needle, and the pad as apackaged kit.
 18. The apparatus of claim 17, further comprising: the atleast one ear needle being one of a plurality of ear needles withopposite proximal and distal ends, the proximal ends of the ear needleseach being adapted for communication with the syringe; the at least oneabsorbent pad being one of a plurality of absorbent pads havingdifferent shapes, each pad of the plurality of absorbent pads beingadapted for communication with a distal end of an ear needle of theplurality of ear needles; and, the packaging containing the plurality ofear needles and the plurality of pads.
 19. The apparatus of claim 18,further comprising: each pad of the plurality of pads being fixed to adistal end of an ear needle of the plurality of ear needles.
 20. Theapparatus of claim 19, further comprising: a diluent carrier; and, thepackaging containing the diluent carrier in the packaged kit.
 21. Theapparatus of claim 19, further comprising: the mitomycin-C having aspecific color.
 22. The apparatus of claim 19, further comprising: themitomycin-C being suspended in an agent that can permeate living tissue.23. A method for application of a pharmaceutical comprising: providing asingle dose of an otologic formulation of mitomycin-C; and, applying thesingle dose of mitomycin-C to interior tissue of an ear canal.
 24. Themethod of claim 23, further comprising: applying the mitomycin-C to atympanic membrane in the ear canal.
 25. The method of claim 23, furthercomprising: suspending the mitomycin-C in a viscous agent.
 26. Themethod of claim 23, further comprising: suspending the mitomycin-C in anadhesive agent that can permeate living tissue.
 27. The method of claim23, further comprising: giving the mitomycin-C a specific color.
 28. Themethod of claim 27, further comprising: applying the mitomycin-C to atympanic membrane in the ear canal.
 29. The method of claim 28, furthercomprising: causing anti-metabolic activity on the tympanic membrane byapplication of the mitomycin-C at a location on the tympanic membranethat is defined by the color of the mitomycin-C.
 30. The method of claim29, further comprising: treating the location on the tympanic membraneby ablating the location with a laser specifically tuned to the color ofthe mitomycin-C.